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• 51. [Article] Inter-annual variability of net primary productivity across multiple spatial scales in the western Oregon Cascades : methods of estimation and examination of spatial coherence

  Quantifying and modeling processes involved in the global carbon cycle is important to evaluate the temporal and spatial variability of these processes and understand the effect of this variability on ...

  Citation × Citation Citation Abstract Copy Title: Inter-annual variability of net primary productivity across multiple spatial scales in the western Oregon Cascades : methods of estimation and examination of spatial coherence Author: Woolley, Travis J. Quantifying and modeling processes involved in the global carbon cycle is important to evaluate the temporal and spatial variability of these processes and understand the effect of this variability on future response to changing climate and land use patterns. Biomass accumulation and Net Primary Productivity (NPP) are large components of ecosystem carbon exchange with the atmosphere and thus are the focus of many modeling efforts. When scaling estimates of NPP temporally from days to years and spatially from square meters to landscapes and regions the spatial coherence of these processes through time must be taken into account. Spatial coherence is the degree to which pairs of sites across space are synchronous (i.e., correlated) through time with respect to a given process or variable. In this thesis I determined the spatial coherence of a major component of NPP, tree bole productivity (NPP[subscript B]), and examine how it influences scaling and our ability to predict NPP and forecast change of this flux. In Chapter 2 I developed and tested a method modeling radial tree increment growth from sub-sampled trees and estimating annual site-level biomass accumulation that allows quantification of the uncertainty in these estimates. Results demonstrated that a simple model using the mean and standard deviation of growth increments underestimated bole biomass increment in all three age classes examined by 1% at the largest sample sizes and up to 15% at the smallest sample sizes. The long term average NPP[subscript B] and inter-annual variability were also underestimated by as much as 10% and 22%, respectively. Stratification of trees by size in sampling and modeling methods increased accuracy and precision of estimates markedly. The precision of both models was sufficient to detect patterns of inter-annual variability. To estimate bole biomass accumulation with acceptable levels of accuracy and precision our results suggest sampling at least 64 trees per site, although one site required a sample size of more than 100 trees. In Chapter 3 I compared year to year variability of NPP for tree boles (NPP[subscript B]) for two adjacent small watersheds (second-growth and old-growth) in the western Cascades of Oregon using the methods developed in Chapter 2. Spatial coherence of NPP[subscript B] within and between watersheds was assessed using multivariate analysis techniques. NPP[subscript B] was found to be less coherent between watersheds than within watersheds, indicating decreased spatial coherence with differences in age class and increased spatial scale. However, a larger degree of spatial coherence existed within the old-growth watershed compared to the second-growth watershed, which may be a result of the smaller degree of variation in environmental characteristics in the former watershed. Within a watershed, potential annual direct incident radiation and heat load were more strongly associated with the variation of NPP[subscript B] than climate. Climatic factors correlated with the temporal variation of annual NPP[subscript B] varied between the two watersheds. Results suggest that inter-annual variability and spatial coherence of forest productivity is a result of both internal (e.g., environment and stand dynamics) and external (climate) factors. An unexpected conclusion was that spatial coherence was not consistent and changed through time. Therefore, the coherence of sites over time is not a simple relationship. Instead the patterns of spatial coherence exhibit complex behaviors that have implications for scaling estimates of productivity. This result also indicates that a correlation coefficient alone may not capture the complexity of change through time across space. In Chapter 4 I estimated year to year variation of NPP[subscript B] for eleven sites of varying age, elevation, moisture, and species composition in the Western Cascades of Oregon. Spatial coherence of tree growth within sites and NPP[subscript B] between sites was assessed using Pearson's product-moment correlation coefficient (r). Results suggest that spatial coherence is highly variable between sites (r=-O.18 to 0.92). The second-growth sites exhibited the greatest temporal variability of annual NPP[subscript B] due to the large accumulation of biomass during stand initiation, but old-growth sites exhibited the greatest variation of coherence of NPP[subscript B] between sites. In some years all sites behaved similarly, but for other years some sites were synchronous while others were not. As growth of individual trees and NPP[subscript B] at the site scale increased, inter-annual variability of those variables increased. Climate in part affected annual NPP[subscript B], but intrinsic factors and spatial proximity also affected the coherence between sites in this landscape. Title: Inter-annual variability of net primary productivity across multiple spatial scales in the western Oregon Cascades : methods of estimation and examination of spatial coherence Author: Woolley, Travis J. Quantifying and modeling processes involved in the global carbon cycle is important to evaluate the temporal and spatial variability of these processes and understand the effect of this variability on future response to changing climate and land use patterns. Biomass accumulation and Net Primary Productivity (NPP) are large components of ecosystem carbon exchange with the atmosphere and thus are the focus of many modeling efforts. When scaling estimates of NPP temporally from days to years and spatially from square meters to landscapes and regions the spatial coherence of these processes through time must be taken into account. Spatial coherence is the degree to which pairs of sites across space are synchronous (i.e., correlated) through time with respect to a given process or variable. In this thesis I determined the spatial coherence of a major component of NPP, tree bole productivity (NPP[subscript B]), and examine how it influences scaling and our ability to predict NPP and forecast change of this flux. In Chapter 2 I developed and tested a method modeling radial tree increment growth from sub-sampled trees and estimating annual site-level biomass accumulation that allows quantification of the uncertainty in these estimates. Results demonstrated that a simple model using the mean and standard deviation of growth increments underestimated bole biomass increment in all three age classes examined by 1% at the largest sample sizes and up to 15% at the smallest sample sizes. The long term average NPP[subscript B] and inter-annual variability were also underestimated by as much as 10% and 22%, respectively. Stratification of trees by size in sampling and modeling methods increased accuracy and precision of estimates markedly. The precision of both models was sufficient to detect patterns of inter-annual variability. To estimate bole biomass accumulation with acceptable levels of accuracy and precision our results suggest sampling at least 64 trees per site, although one site required a sample size of more than 100 trees. In Chapter 3 I compared year to year variability of NPP for tree boles (NPP[subscript B]) for two adjacent small watersheds (second-growth and old-growth) in the western Cascades of Oregon using the methods developed in Chapter 2. Spatial coherence of NPP[subscript B] within and between watersheds was assessed using multivariate analysis techniques. NPP[subscript B] was found to be less coherent between watersheds than within watersheds, indicating decreased spatial coherence with differences in age class and increased spatial scale. However, a larger degree of spatial coherence existed within the old-growth watershed compared to the second-growth watershed, which may be a result of the smaller degree of variation in environmental characteristics in the former watershed. Within a watershed, potential annual direct incident radiation and heat load were more strongly associated with the variation of NPP[subscript B] than climate. Climatic factors correlated with the temporal variation of annual NPP[subscript B] varied between the two watersheds. Results suggest that inter-annual variability and spatial coherence of forest productivity is a result of both internal (e.g., environment and stand dynamics) and external (climate) factors. An unexpected conclusion was that spatial coherence was not consistent and changed through time. Therefore, the coherence of sites over time is not a simple relationship. Instead the patterns of spatial coherence exhibit complex behaviors that have implications for scaling estimates of productivity. This result also indicates that a correlation coefficient alone may not capture the complexity of change through time across space. In Chapter 4 I estimated year to year variation of NPP[subscript B] for eleven sites of varying age, elevation, moisture, and species composition in the Western Cascades of Oregon. Spatial coherence of tree growth within sites and NPP[subscript B] between sites was assessed using Pearson's product-moment correlation coefficient (r). Results suggest that spatial coherence is highly variable between sites (r=-O.18 to 0.92). The second-growth sites exhibited the greatest temporal variability of annual NPP[subscript B] due to the large accumulation of biomass during stand initiation, but old-growth sites exhibited the greatest variation of coherence of NPP[subscript B] between sites. In some years all sites behaved similarly, but for other years some sites were synchronous while others were not. As growth of individual trees and NPP[subscript B] at the site scale increased, inter-annual variability of those variables increased. Climate in part affected annual NPP[subscript B], but intrinsic factors and spatial proximity also affected the coherence between sites in this landscape. Close

• 52. [Article] Downstream Warming and Headwater Acidity May Diminish Coldwater Habitat in Southern Appalachian Mountain Streams

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Public Library ...

  Citation × Citation Citation Abstract Copy Title: Downstream Warming and Headwater Acidity May Diminish Coldwater Habitat in Southern Appalachian Mountain Streams Author: Sullivan, T. J., McDonnell, T. C., et al., Sloat, M. R. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Title: Downstream Warming and Headwater Acidity May Diminish Coldwater Habitat in Southern Appalachian Mountain Streams Author: Sullivan, T. J., McDonnell, T. C., et al., Sloat, M. R. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Close

• 53. [Article] Assessing cumulative influences of watershed-scale landuses on reed canarygrass (Phalaris arundinacea L.) abundance

  The West Eugene Wetlands, Eugene, Oregon, which provide habitat for number of endemic and endangered plant species, are currently threatened by a Reed canarygrass (Phalaris arundinacea L.) invasion. This ...

  Citation × Citation Citation Abstract Copy Title: Assessing cumulative influences of watershed-scale landuses on reed canarygrass (Phalaris arundinacea L.) abundance Author: Inahara, Satomi The West Eugene Wetlands, Eugene, Oregon, which provide habitat for number of endemic and endangered plant species, are currently threatened by a Reed canarygrass (Phalaris arundinacea L.) invasion. This study addresses the hypothesis that Phalaris spread can be explained in part by using watershed-scale landuse patterns as surrogates of the water quality and hydrologic regime in the associated watersheds. A multiple regression model was constructed to test the effects of watershed-scale landuses on Phalaris abundance. The spatially referenced landuse attributes were estimated using accumulated inverse-squared flow path distances between each wetland and cells in a grid-based representation of landuse/cover data in a Geographic Information System. The locally measured physical and biological characteristics of wetlands were also incorporated into the model to adjust for site differences. Bias in the estimated parametric coefficients were found to be negligible using 1,000 iterations of a bootstrap re-sampling technique. Bias-corrected-and-accelerated intervals also supported the significance of these estimates. The inferential model, consisting of the percentage open water cover in the wetlands, an indicator of highly disturbed site and watershed-scale urban and forest landuses, explained 67 percent variation of Phalaris abundance. There was convincing evidence that the cumulative watershed-scale landuse patterns affected Phalaris abundance (p-value < 0.001; extra-sum-of-squares F-test). In particular, urbanization was strongly associated with greater Phalaris abundance (p-value = 0.00001, two-sided t-test). The effects of watershed-scale landuse appeared to be persistent in the inside of the wetland edges. Implications for wetland management were discussed. Alternative restoration strategy addressing plant diversity was also proposed. Title: Assessing cumulative influences of watershed-scale landuses on reed canarygrass (Phalaris arundinacea L.) abundance Author: Inahara, Satomi The West Eugene Wetlands, Eugene, Oregon, which provide habitat for number of endemic and endangered plant species, are currently threatened by a Reed canarygrass (Phalaris arundinacea L.) invasion. This study addresses the hypothesis that Phalaris spread can be explained in part by using watershed-scale landuse patterns as surrogates of the water quality and hydrologic regime in the associated watersheds. A multiple regression model was constructed to test the effects of watershed-scale landuses on Phalaris abundance. The spatially referenced landuse attributes were estimated using accumulated inverse-squared flow path distances between each wetland and cells in a grid-based representation of landuse/cover data in a Geographic Information System. The locally measured physical and biological characteristics of wetlands were also incorporated into the model to adjust for site differences. Bias in the estimated parametric coefficients were found to be negligible using 1,000 iterations of a bootstrap re-sampling technique. Bias-corrected-and-accelerated intervals also supported the significance of these estimates. The inferential model, consisting of the percentage open water cover in the wetlands, an indicator of highly disturbed site and watershed-scale urban and forest landuses, explained 67 percent variation of Phalaris abundance. There was convincing evidence that the cumulative watershed-scale landuse patterns affected Phalaris abundance (p-value < 0.001; extra-sum-of-squares F-test). In particular, urbanization was strongly associated with greater Phalaris abundance (p-value = 0.00001, two-sided t-test). The effects of watershed-scale landuse appeared to be persistent in the inside of the wetland edges. Implications for wetland management were discussed. Alternative restoration strategy addressing plant diversity was also proposed. Close

• 54. [Article] Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho

  In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders ...

  Citation × Citation Citation Abstract Copy Title: Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho Author: Inouye, Allison Marshall In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and identify strategies that may help mitigate the impacts. The 8,300 square kilometer region in central Idaho contains a mixture of public and private land ownership, a diversity of landcover ranging from steep forested headwaters to expansive desert shrublands to a concentrated area of urban development that has experienced a quadrupling of population since the 1970s. With nearly 60% of precipitation falling as winter snow, stakeholders expressed concern regarding the vulnerability of the quantity and timing of seasonal snowpack as well as surface water supplies used primarily for agricultural irrigation under projected climate change. Here, we achieve two objectives. The first is the development of a hydrologic model to represent the dynamics of the surface water system in the Big Wood Basin. We use the semi-distributed model Envision-Flow to represent surface water hydrology, reservoir operations, and agricultural irrigation. We calibrated the model using a multi-criteria objective function that considered three metrics related to streamflow and one metric related to snow water equivalent. The model achieved higher an efficiency of 0.74 for the main stem of the Big Wood River and 0.50 for the Camas Creek tributary during the validation period. The second objective is an analysis of the Big Wood Basin hydrology under alternative future climate scenarios. We forced the calibrated model with three downscaled CMIP5 climate model inputs representing a range of possible future conditions over the period 2010-2070. The climate models simulate an increase in basin average annual air temperature ranging from 1.6-5.7oC in the 2060s compared to the 1980-2009 average. The climate models show less of a clear trend regarding precipitation but in general, one model simulates precipitation patterns similar to historic, one is slightly wetter than historic, and one is slightly drier than historic by the mid-21st century. Under these future climate scenarios, the depth of April 1 SWE may decline by as much as 92% in the 2060s compared to the historic average. Mid to high elevations exhibit the largest reductions in SWE. Simulated streamflows show a shift in timing, with peak flows occurring up to three weeks earlier and center of timing from two to seven weeks earlier in the 2050-2069 period compared to the historic period. Reduced peak flows of 14-70% were simulated by mid-century. The simulated total annual streamflow, though, fell within the historic interquartile range for most years in the future period. These and other metrics considered suggest that the surface water hydrology of the Big Wood Basin is likely to be impacted by climate change. If the natural water storage provided by the annual snowpack is reduced and timing of streamflows shifts, water resource use and management may need to change in the future. This work provides a foundation from which to explore alternative management scenarios. The approach used here can be transferred to other watersheds to further assess how water resources may be affected by climate change. Title: Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho Author: Inouye, Allison Marshall In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and identify strategies that may help mitigate the impacts. The 8,300 square kilometer region in central Idaho contains a mixture of public and private land ownership, a diversity of landcover ranging from steep forested headwaters to expansive desert shrublands to a concentrated area of urban development that has experienced a quadrupling of population since the 1970s. With nearly 60% of precipitation falling as winter snow, stakeholders expressed concern regarding the vulnerability of the quantity and timing of seasonal snowpack as well as surface water supplies used primarily for agricultural irrigation under projected climate change. Here, we achieve two objectives. The first is the development of a hydrologic model to represent the dynamics of the surface water system in the Big Wood Basin. We use the semi-distributed model Envision-Flow to represent surface water hydrology, reservoir operations, and agricultural irrigation. We calibrated the model using a multi-criteria objective function that considered three metrics related to streamflow and one metric related to snow water equivalent. The model achieved higher an efficiency of 0.74 for the main stem of the Big Wood River and 0.50 for the Camas Creek tributary during the validation period. The second objective is an analysis of the Big Wood Basin hydrology under alternative future climate scenarios. We forced the calibrated model with three downscaled CMIP5 climate model inputs representing a range of possible future conditions over the period 2010-2070. The climate models simulate an increase in basin average annual air temperature ranging from 1.6-5.7oC in the 2060s compared to the 1980-2009 average. The climate models show less of a clear trend regarding precipitation but in general, one model simulates precipitation patterns similar to historic, one is slightly wetter than historic, and one is slightly drier than historic by the mid-21st century. Under these future climate scenarios, the depth of April 1 SWE may decline by as much as 92% in the 2060s compared to the historic average. Mid to high elevations exhibit the largest reductions in SWE. Simulated streamflows show a shift in timing, with peak flows occurring up to three weeks earlier and center of timing from two to seven weeks earlier in the 2050-2069 period compared to the historic period. Reduced peak flows of 14-70% were simulated by mid-century. The simulated total annual streamflow, though, fell within the historic interquartile range for most years in the future period. These and other metrics considered suggest that the surface water hydrology of the Big Wood Basin is likely to be impacted by climate change. If the natural water storage provided by the annual snowpack is reduced and timing of streamflows shifts, water resource use and management may need to change in the future. This work provides a foundation from which to explore alternative management scenarios. The approach used here can be transferred to other watersheds to further assess how water resources may be affected by climate change. Close

• 55. [Article] The application of spatial data analysis and visualization in the development of landscape indicators to assess stream conditions

  The main theme of this research is the application of geographic techniques in a study involving environmental monitoring and analysis of the associations between landscape and in-stream characteristics ...

  Citation × Citation Citation Abstract Copy Title: The application of spatial data analysis and visualization in the development of landscape indicators to assess stream conditions Author: Buckley, Aileen R. The main theme of this research is the application of geographic techniques in a study involving environmental monitoring and analysis of the associations between landscape and in-stream characteristics in the Pacific Northwest. The geographic techniques used in this study include (1) geographic information systems (GIS) coupled with statistical analysis and (2) geographic visualization. The study area comprised 44 stream sampling sites and their respective watersheds in the Willamette River Basin of western Oregon. The first paper in this dissertation is a literature review of scientific visualization relative to the field of geography. Integrating more traditional techniques of cartographic lineage with new methods of geographic visualization, this chapter introduces terminology related to geographic visualization as well as a variety of methods for the visualization of multivariate spatial data. The second paper describes the use of scientific visualization to generate a composite indicator of landscape stress (i.e., a robust metric that represents multiple integrated characteristics of landscape disturbance). Through a unique approach, the power of the human visual system was used to synthesize multiple attributes of the landscape in mean ranks of watershed stress. Participants in this study were consistently able to distinguish between sites, and they were generally in agreement on how to rank sites. The final paper describes the more traditional "lumped landscape" approach to indicator development and examines inherent scale properties of spatial data that may affect the generation of landscape indicators as well as the outcomes of statistical and GIS analyses in which they are used. In this study, grain (the finest level of resolution), extent (the area under consideration), and level of generalization in classification were systematically manipulated to determine effects of varying spatial scale properties on the generation of landscape metrics. Resolution of the data sets and differences between sites accounted for most of the variation in the landscape indicators generated. Together these three papers describe and demonstrate the important role that geographic techniques, in particular GIS coupled with statistical analysis and visualization can play in better understanding our environment. Title: The application of spatial data analysis and visualization in the development of landscape indicators to assess stream conditions Author: Buckley, Aileen R. The main theme of this research is the application of geographic techniques in a study involving environmental monitoring and analysis of the associations between landscape and in-stream characteristics in the Pacific Northwest. The geographic techniques used in this study include (1) geographic information systems (GIS) coupled with statistical analysis and (2) geographic visualization. The study area comprised 44 stream sampling sites and their respective watersheds in the Willamette River Basin of western Oregon. The first paper in this dissertation is a literature review of scientific visualization relative to the field of geography. Integrating more traditional techniques of cartographic lineage with new methods of geographic visualization, this chapter introduces terminology related to geographic visualization as well as a variety of methods for the visualization of multivariate spatial data. The second paper describes the use of scientific visualization to generate a composite indicator of landscape stress (i.e., a robust metric that represents multiple integrated characteristics of landscape disturbance). Through a unique approach, the power of the human visual system was used to synthesize multiple attributes of the landscape in mean ranks of watershed stress. Participants in this study were consistently able to distinguish between sites, and they were generally in agreement on how to rank sites. The final paper describes the more traditional "lumped landscape" approach to indicator development and examines inherent scale properties of spatial data that may affect the generation of landscape indicators as well as the outcomes of statistical and GIS analyses in which they are used. In this study, grain (the finest level of resolution), extent (the area under consideration), and level of generalization in classification were systematically manipulated to determine effects of varying spatial scale properties on the generation of landscape metrics. Resolution of the data sets and differences between sites accounted for most of the variation in the landscape indicators generated. Together these three papers describe and demonstrate the important role that geographic techniques, in particular GIS coupled with statistical analysis and visualization can play in better understanding our environment. Close

• 56. [Article] Uncertainty in forest road hydrologic modeling and catchment scale assessment of forest road sediment yield

  The goal of this study was to advance methods for assessment of forest road hydrologic response and sediment yield at a catchment scale. This research looked at the effect of soil depth estimation on the ...

  Citation × Citation Citation Abstract Copy Title: Uncertainty in forest road hydrologic modeling and catchment scale assessment of forest road sediment yield Author: Surfleet, Christopher G. The goal of this study was to advance methods for assessment of forest road hydrologic response and sediment yield at a catchment scale. This research looked at the effect of soil depth estimation on the Distributive Hydrology Soil Vegetation Model (DHSVM), assessed the uncertainty and accuracy of hydrologic modeling of forest roads by DHSVM, and evaluated the use of road runoff and sediment sampling for catchment scale road sediment estimates. The influence of soil depth estimation on DHSVM varied by spatial scale and hydrologic process modeled. Soil depth measurement improved DHSVM simulated streamflow and road ditchflow for the rising limb of the hydrograph with no improvements during baseflow. For site specific or small scale modeling a deterministic soil depth model fit to field measurements was best. For larger scale simulations of streamflow mean soil depth provided as good or better estimates. Considerable uncertainty in estimates of road hydrologic response was observed from DHSVM. DHSVM over predicted individual road discharges. As the spatial scale and temporal scale was increased the uncertainty in DHSVM results decreased. This suggests that model structures chosen for DHSVM would be better determined with internal catchment data, at smaller scales. The GLUE assessment showed that change detection analysis with DHSVM will be limited to sites or scales of the catchment that behavioral model structures can be identified. From this research it was determined that only the catchment scale simulations and a few individual road locations could be used for change detection. The storm runoff volumes and peak flows from road ditchflow had linear relationships with storm sediment load. These relationships had to be developed by classes of road locations and types in an intensively managed forest due to variability in road design, hydrologic response, and road use. Sediment from roads estimated from field measurements used with SEDMODL2 or WARSEM provided substantially lower estimates than without field measured adjustments. The use of road runoff for sediment estimation provided even lower catchment scale sediment results. DHSVM simulated road runoff for sediment estimation provided catchment scale results similar to the sediment yield estimated from observed road runoff. Title: Uncertainty in forest road hydrologic modeling and catchment scale assessment of forest road sediment yield Author: Surfleet, Christopher G. The goal of this study was to advance methods for assessment of forest road hydrologic response and sediment yield at a catchment scale. This research looked at the effect of soil depth estimation on the Distributive Hydrology Soil Vegetation Model (DHSVM), assessed the uncertainty and accuracy of hydrologic modeling of forest roads by DHSVM, and evaluated the use of road runoff and sediment sampling for catchment scale road sediment estimates. The influence of soil depth estimation on DHSVM varied by spatial scale and hydrologic process modeled. Soil depth measurement improved DHSVM simulated streamflow and road ditchflow for the rising limb of the hydrograph with no improvements during baseflow. For site specific or small scale modeling a deterministic soil depth model fit to field measurements was best. For larger scale simulations of streamflow mean soil depth provided as good or better estimates. Considerable uncertainty in estimates of road hydrologic response was observed from DHSVM. DHSVM over predicted individual road discharges. As the spatial scale and temporal scale was increased the uncertainty in DHSVM results decreased. This suggests that model structures chosen for DHSVM would be better determined with internal catchment data, at smaller scales. The GLUE assessment showed that change detection analysis with DHSVM will be limited to sites or scales of the catchment that behavioral model structures can be identified. From this research it was determined that only the catchment scale simulations and a few individual road locations could be used for change detection. The storm runoff volumes and peak flows from road ditchflow had linear relationships with storm sediment load. These relationships had to be developed by classes of road locations and types in an intensively managed forest due to variability in road design, hydrologic response, and road use. Sediment from roads estimated from field measurements used with SEDMODL2 or WARSEM provided substantially lower estimates than without field measured adjustments. The use of road runoff for sediment estimation provided even lower catchment scale sediment results. DHSVM simulated road runoff for sediment estimation provided catchment scale results similar to the sediment yield estimated from observed road runoff. Close

• 57. [Article] Multiscale assessment of thermal patterns and the distribution of chinook salmon in the John Day River Basin, Oregon

  This study examined the distribution and behavior of adult spring chinook salmon (Oncorhynchus tshawytscha) related to patterns of stream temperature and physical habitat at channel unit, reach, and basin-wide ...

  Citation × Citation Citation Abstract Copy Title: Multiscale assessment of thermal patterns and the distribution of chinook salmon in the John Day River Basin, Oregon Author: Torgersen, Christian E. This study examined the distribution and behavior of adult spring chinook salmon (Oncorhynchus tshawytscha) related to patterns of stream temperature and physical habitat at channel unit, reach, and basin-wide spatial scales in both a wilderness stream and a disturbed stream in the John Day River basin in northeastern Oregon. Thermal remote sensing of holding and spawning reaches in the upper subbasins of the North Fork and Middle Fork John Day River provided spatially continuous maps of stream temperature. Multiscale associations between salmon and cool-water areas were assessed by overlaying thermal imagery with fish locations mapped during distributional surveys. Chinook salmon were distributed non-uniformly throughout each study area, indicating that salmon selected certain reaches within each subbasin. The coldest reaches available to salmon within the Middle Fork study areas were low gradient, unconstrained reaches where the cooling influence of groundwater flow was the most apparent. In the Middle Fork, the stream currently managed for grazing and timber harvest, water temperature differences were typically 1-2°C within riffle-pool sequences and 3-4°C among reaches. The reach level association between salmon distribution and stream temperature patterns at channel unit and reach level spatial scales was strongest in the warmest study reach, the Middle Fork, and weakest in the coldest study reach, the North Fork. Pools were the preferred habitat for adult spring chinook in both subbasins; however, riffles were used more in the North Fork, the coldest subbasin. This study identified the problems and also the benefits associated with stream temperature patchiness, or discontinuity, both in currently disturbed and in recovering riverine ecosystems. Connectivity among system components in aquatic ecosystems is generally considered necessary for maintaining long-term ecological health. However, it is heterogeneity in the landscape/hydrogeologic template that creates refuge patches in disturbed stream ecosystems, such as those in the John Day River basin. Our observations of thermal refugia occurring at multiple spatial scales, particularly in the Middle Fork John Day River, indicate that, although discontinuity may be an ecological warning sign, refuge patches in streams should also be viewed as expressions of restoration potential because they are functioning remnants of a once continuous, intact hydrologic system. Title: Multiscale assessment of thermal patterns and the distribution of chinook salmon in the John Day River Basin, Oregon Author: Torgersen, Christian E. This study examined the distribution and behavior of adult spring chinook salmon (Oncorhynchus tshawytscha) related to patterns of stream temperature and physical habitat at channel unit, reach, and basin-wide spatial scales in both a wilderness stream and a disturbed stream in the John Day River basin in northeastern Oregon. Thermal remote sensing of holding and spawning reaches in the upper subbasins of the North Fork and Middle Fork John Day River provided spatially continuous maps of stream temperature. Multiscale associations between salmon and cool-water areas were assessed by overlaying thermal imagery with fish locations mapped during distributional surveys. Chinook salmon were distributed non-uniformly throughout each study area, indicating that salmon selected certain reaches within each subbasin. The coldest reaches available to salmon within the Middle Fork study areas were low gradient, unconstrained reaches where the cooling influence of groundwater flow was the most apparent. In the Middle Fork, the stream currently managed for grazing and timber harvest, water temperature differences were typically 1-2°C within riffle-pool sequences and 3-4°C among reaches. The reach level association between salmon distribution and stream temperature patterns at channel unit and reach level spatial scales was strongest in the warmest study reach, the Middle Fork, and weakest in the coldest study reach, the North Fork. Pools were the preferred habitat for adult spring chinook in both subbasins; however, riffles were used more in the North Fork, the coldest subbasin. This study identified the problems and also the benefits associated with stream temperature patchiness, or discontinuity, both in currently disturbed and in recovering riverine ecosystems. Connectivity among system components in aquatic ecosystems is generally considered necessary for maintaining long-term ecological health. However, it is heterogeneity in the landscape/hydrogeologic template that creates refuge patches in disturbed stream ecosystems, such as those in the John Day River basin. Our observations of thermal refugia occurring at multiple spatial scales, particularly in the Middle Fork John Day River, indicate that, although discontinuity may be an ecological warning sign, refuge patches in streams should also be viewed as expressions of restoration potential because they are functioning remnants of a once continuous, intact hydrologic system. Close

• 58. [Article] Potential for dispersal of the non-native parasite Myxobolus cerebralis : qualitative risk assessments for the state of Alaska and the Willamette River Basin, Oregon

  First introduced to the USA in 1958, Myxobolus cerebralis, the parasite responsible for whirling disease in salmonids, has since spread across the country causing severe declines in wild trout populations ...

  Citation × Citation Citation Abstract Copy Title: Potential for dispersal of the non-native parasite Myxobolus cerebralis : qualitative risk assessments for the state of Alaska and the Willamette River Basin, Oregon Author: Arsan, E. Leyla First introduced to the USA in 1958, Myxobolus cerebralis, the parasite responsible for whirling disease in salmonids, has since spread across the country causing severe declines in wild trout populations in the intermountain west. Recent development of risk assessment models used to assess the likelihood and consequences of exotic parasite introduction, have strengthened the process of science-based decision-making in aquatic animal health. In the case of M. cerebralis, it is necessary to use a risk assessment model with two unique segments that clearly address the distinct life stages and respective hosts of the parasite separately. The studies described examine the probability of M. cerebralis introduction and establishment for two regions: the state of Alaska, and the Willamette River basin, Oregon. The Alaska risk assessment was based on the assumption that the parasite did not already occur in the state. However, in the process of validating this assumption, we documented the first polymerase chain reaction (PCR) detection of the parasite in the state. The pathogen was identified in hatchery rainbow trout (Oncorhynchus mykiss) from the Anchorage area. Although this is the first detection of the parasite in Alaska, clinical whirling disease has never been documented in the state. To qualitatively assess the risk of further spread of M. cerebralis in Alaska, four potential routes of dissemination were examined: movement of fish by humans, natural dispersal (via migratory birds and stray anadromous salmon), recreational activities, and commercial seafood processing. This research indicates the most likely pathway for M. cerebralis transport in Alaska is human movement of fish. In the Willamette River basin, Oregon, introduction of M. cerebralis has already occurred, though establishment appears limited to a single private hatchery. Introduction in this region was considered the most likely to occur as a result of human movements of fish. Straying anadromous salmonids were also assessed and were present in higher numbers than predicted. However, they were not infected with the parasite, and thus the probability for introduction by this route is low. The probability of introduction of the parasite varies throughout the Willamette River basin. Areas with the highest probability for M. cerebralis introduction were identified as the Clackamas and Santiam River subbasins. The Clackamas River has already experienced an introduction of the parasite, has the largest concentration of hatcheries (state, federal, and private), has a popular sport fishery, and is the closest major tributary to the enormous piscivorous bird-populations in the Columbia River estuary. The Santiam subbasin has a popular sport fishery, received the highest number of stray fish in the Willamette River basin, and has the second largest concentration of hatcheries in the Willamette River basin. Unique from introduction, establishment of the parasite is dependent upon several environmental and biological factors including: water temperatures, spatial/temporal overlap of hosts, and the distribution and genetic composition of the parasite’s invertebrate host, Tubifex tubifex. The distribution, genetic composition and susceptibility of T. tubifex, were considered the most important factor in the ability of M. cerebralis to establish in both systems. Surveys of oligochaete populations were conducted in both study regions. In Alaska, T. tubifex was not detected from the southeast region and the apparent lack of appropriate tubificid hosts may prevent establishment in that part of the state. However, 4 lineages (I, III, IV, and VI) of the species were identified from southcentral Alaska. Lineage IV has not been previously been described in North America and its susceptibility to M. cerebralis was unknown. When lineage IV T. tubifex and 3 mixed-lineage (I, III, IV and VI) groups were exposed to M. cerebralis, only lineage III became infected under our experimental conditions. Thus, if the parasite were dispersed, conditions are appropriate for establishment and propagation of the parasite life cycle in southcentral Alaska, although detrimental effects on fish populations may be reduced as a result of the presence of non-susceptible lineages of T. tubifex. The probability of further establishment in this area is greatest in Ship Creek, where the abundance of susceptible T. tubifex, the presence of susceptible rainbow trout (Oncorhynchus mykiss), and the proximity to the known area of infection make conditions particularly appropriate. Similar to findings in Alaska, the Willamette River basin, Oregon also supports populations of susceptible T. tubifex. If the pathogen were introduced, probability of establishment is high in certain areas of the basin as all conditions are appropriate for propagation of the parasite life cycle. Tributaries to the mainstem Willamette River have the highest probability of establishment as these areas have the greatest numbers of susceptible T. tubifex. However, the abundance of resistant strains of T. tubifex could mitigate the effects of M. cerebralis if introduced. Management recommendations to reduce the likelihood of parasite dissemination are similar for Oregon and Alaska since human movement of fish and angler activities were considered the most likely routes of introduction for both regions. Based on this research, steps should also be taken to limit human movement of fish, whether by restricting carcass planting for stream enrichment in Oregon, or by prohibiting use of fish heads as bait in southcentral Alaska. The states should also allot resources to angler education and awareness of the effects of angler activity and recreation on dispersal of M. cerebralis. This could be done using a combination of brochures and signage at boat ramps describing how to prevent spread of aquatic nuisance species. Title: Potential for dispersal of the non-native parasite Myxobolus cerebralis : qualitative risk assessments for the state of Alaska and the Willamette River Basin, Oregon Author: Arsan, E. Leyla First introduced to the USA in 1958, Myxobolus cerebralis, the parasite responsible for whirling disease in salmonids, has since spread across the country causing severe declines in wild trout populations in the intermountain west. Recent development of risk assessment models used to assess the likelihood and consequences of exotic parasite introduction, have strengthened the process of science-based decision-making in aquatic animal health. In the case of M. cerebralis, it is necessary to use a risk assessment model with two unique segments that clearly address the distinct life stages and respective hosts of the parasite separately. The studies described examine the probability of M. cerebralis introduction and establishment for two regions: the state of Alaska, and the Willamette River basin, Oregon. The Alaska risk assessment was based on the assumption that the parasite did not already occur in the state. However, in the process of validating this assumption, we documented the first polymerase chain reaction (PCR) detection of the parasite in the state. The pathogen was identified in hatchery rainbow trout (Oncorhynchus mykiss) from the Anchorage area. Although this is the first detection of the parasite in Alaska, clinical whirling disease has never been documented in the state. To qualitatively assess the risk of further spread of M. cerebralis in Alaska, four potential routes of dissemination were examined: movement of fish by humans, natural dispersal (via migratory birds and stray anadromous salmon), recreational activities, and commercial seafood processing. This research indicates the most likely pathway for M. cerebralis transport in Alaska is human movement of fish. In the Willamette River basin, Oregon, introduction of M. cerebralis has already occurred, though establishment appears limited to a single private hatchery. Introduction in this region was considered the most likely to occur as a result of human movements of fish. Straying anadromous salmonids were also assessed and were present in higher numbers than predicted. However, they were not infected with the parasite, and thus the probability for introduction by this route is low. The probability of introduction of the parasite varies throughout the Willamette River basin. Areas with the highest probability for M. cerebralis introduction were identified as the Clackamas and Santiam River subbasins. The Clackamas River has already experienced an introduction of the parasite, has the largest concentration of hatcheries (state, federal, and private), has a popular sport fishery, and is the closest major tributary to the enormous piscivorous bird-populations in the Columbia River estuary. The Santiam subbasin has a popular sport fishery, received the highest number of stray fish in the Willamette River basin, and has the second largest concentration of hatcheries in the Willamette River basin. Unique from introduction, establishment of the parasite is dependent upon several environmental and biological factors including: water temperatures, spatial/temporal overlap of hosts, and the distribution and genetic composition of the parasite’s invertebrate host, Tubifex tubifex. The distribution, genetic composition and susceptibility of T. tubifex, were considered the most important factor in the ability of M. cerebralis to establish in both systems. Surveys of oligochaete populations were conducted in both study regions. In Alaska, T. tubifex was not detected from the southeast region and the apparent lack of appropriate tubificid hosts may prevent establishment in that part of the state. However, 4 lineages (I, III, IV, and VI) of the species were identified from southcentral Alaska. Lineage IV has not been previously been described in North America and its susceptibility to M. cerebralis was unknown. When lineage IV T. tubifex and 3 mixed-lineage (I, III, IV and VI) groups were exposed to M. cerebralis, only lineage III became infected under our experimental conditions. Thus, if the parasite were dispersed, conditions are appropriate for establishment and propagation of the parasite life cycle in southcentral Alaska, although detrimental effects on fish populations may be reduced as a result of the presence of non-susceptible lineages of T. tubifex. The probability of further establishment in this area is greatest in Ship Creek, where the abundance of susceptible T. tubifex, the presence of susceptible rainbow trout (Oncorhynchus mykiss), and the proximity to the known area of infection make conditions particularly appropriate. Similar to findings in Alaska, the Willamette River basin, Oregon also supports populations of susceptible T. tubifex. If the pathogen were introduced, probability of establishment is high in certain areas of the basin as all conditions are appropriate for propagation of the parasite life cycle. Tributaries to the mainstem Willamette River have the highest probability of establishment as these areas have the greatest numbers of susceptible T. tubifex. However, the abundance of resistant strains of T. tubifex could mitigate the effects of M. cerebralis if introduced. Management recommendations to reduce the likelihood of parasite dissemination are similar for Oregon and Alaska since human movement of fish and angler activities were considered the most likely routes of introduction for both regions. Based on this research, steps should also be taken to limit human movement of fish, whether by restricting carcass planting for stream enrichment in Oregon, or by prohibiting use of fish heads as bait in southcentral Alaska. The states should also allot resources to angler education and awareness of the effects of angler activity and recreation on dispersal of M. cerebralis. This could be done using a combination of brochures and signage at boat ramps describing how to prevent spread of aquatic nuisance species. Close

• 59. [Article] Culvert assessment

  The Lower Nehalem Watershed Council utilized information from several sources to identify culverts in the watershed that are most likely to block migration of Coho. Our approach builds upon the GIS data ...

  Citation × Citation Citation Abstract Copy Title: Culvert assessment The Lower Nehalem Watershed Council utilized information from several sources to identify culverts in the watershed that are most likely to block migration of Coho. Our approach builds upon the GIS data layers provided by Portland State as part of their assessment of the watershed. Additional data layers were obtained from the Bureau of Land Management (BLM) and Coastal Landscape Analysis Modeling Study (CLAMS). Title: Culvert assessment The Lower Nehalem Watershed Council utilized information from several sources to identify culverts in the watershed that are most likely to block migration of Coho. Our approach builds upon the GIS data layers provided by Portland State as part of their assessment of the watershed. Additional data layers were obtained from the Bureau of Land Management (BLM) and Coastal Landscape Analysis Modeling Study (CLAMS). Close

• 60. [Article] Silvies sub-basin assessment

  Citation × Citation Citation Abstract Copy Title: Silvies sub-basin assessment Author: Harney County Watershed Council, Maupin, Erin Title: Silvies sub-basin assessment Author: Harney County Watershed Council, Maupin, Erin Close